powder coat vs sandblasting and paint

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I think you will be surprised by how long wire wheels take to thoroughly blast. I remember my dad doing some Model A wheels when I was a kid and he stacked them up so that as he blasted, it hit them all. The ones on the bottom obviously didnt get super clean that way but as he finished the top one the one below it was also mostly done and so on. I thought it was pretty smart anyway.

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Four wheels in a few hours in your driveway? Yeah if you want to just knock some of the rust and paint off, unless you have a big commercial rig I find that hard to believe. But then again when I'm done you can't see any paint or rust on any part of the wheel inside or out. When you are wearing the hood it probably all looks good through that little window that's all etched up. I think I spent 4 hours in my driveways on the first 40 Ford rim I ever did and it wasn't spotless. No sense in doing it unless you are going to strip it all down bare. What you leave will fail. If you are using pool sand as well it's going to take a while if it even works. I've done alot of blasting in my cabinet and even stuff like a 4 blade fan seems to take atleast 1/2 an hour or more. I always said having a blast cabinet is almost a curse as you tend to blast everything and spend alot of time in it that you weren't planning on.

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I purchased this set of 4 1930 Marmon 19" wheels with the thought I might use them on a '31 CD8 Chrysler project I am rebuilding (same hubcap inner diameter)(since decided I am not using them as I found correct wheels). Since I was planning on a driver quality car, I decided to simply get them powder-coated black, including getting the lock-rings powder-coated in chrome. The shop offered to do all 4 for about $325US, including sandblasting and coating, but with no further labor for "smoothing". Wheels came back in perfect gloss black, but they were excellent to start with. In hindsight, I should have spent some time on the lock-rings smoothing out pitting and minor damage, since powder chrome only works well for a super smooth base. Much safer to put lock-rings on powdered than on painted wheels. I know a colleague who decided many years ago to do a high quality paint job on similar wheels. He said he spent 40 hours on each wheel smoothing out runs and missed spots, and had to apply 10 coats of paint to get a wonderful finish. So nothing is easy, but powder-coating sure gives a harder and more uniform finish at likely lower overall cost (unless you are doing it yourself with a rattle can).

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Four wheels in a few hours in your driveway? Yeah if you want to just knock some of the rust and paint off, unless you have a big commercial rig I find that hard to believe. But then again when I'm done you can't see any paint or rust on any part of the wheel inside or out. When you are wearing the hood it probably all looks good through that little window that's all etched up. I think I spent 4 hours in my driveways on the first 40 Ford rim I ever did and it wasn't spotless. No sense in doing it unless you are going to strip it all down bare. What you leave will fail. If you are using pool sand as well it's going to take a while if it even works. I've done alot of blasting in my cabinet and even stuff like a 4 blade fan seems to take atleast 1/2 an hour or more. I always said having a blast cabinet is almost a curse as you tend to blast everything and spend alot of time in it that you weren't planning on.

Much of my blasting is documented in my restoration thread. Just used the 5 gallon blaster from Harbor Freight. The photos show how thorough I am. Everything in the car was brought to bare metal. If you have the right grade of blasting material shot out of the right nozzle, it goes pretty quick. Here is a sample pic of the frame detail and the setup in the driveway. The frame took a full day.

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Much of my blasting is documented in my restoration thread. Just used the 5 gallon blaster from Harbor Freight. The photos show how thorough I am. Everything in the car was brought to bare metal. If you have the right grade of blasting material shot out of the right nozzle, it goes pretty quick. Here is a sample pic of the frame detail and the setup in the driveway. The frame took a full day.

Thats impressive. I started with a small sandblaster like that but eventually upgraded to a larger model with wheels that I got from harbor freight. I think it holds 160 pounds of sand. I can blast a looooooonnnnggg time with it. It really sped up the job just because you dont have to stop and refil nearly as often. It probably cut my blasting time in half.

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That frame had to have had very light surface rust to get it done in a day. Especially with having to pick up all the sand and sift it back in the pot. I have never gotten that kind of production out of my cabinet with a good compressor and the sand constantly recycling. My cabinet is the TP tools 976 I believe detailer with a bunch of upgrades.

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That frame had to have had very light surface rust to get it done in a day. Especially with having to pick up all the sand and sift it back in the pot. I have never gotten that kind of production out of my cabinet with a good compressor and the sand constantly recycling. My cabinet is the TP tools 976 I believe detailer with a bunch of upgrades.

From what I can see on the cross rails, it looks to be pretty light surface rust and in great shape overall. I've been humming and hawing over deciding to do my frame myself with my no-name blaster pot I have that's been good for small parts, upgrade to something a little more capable, or farm that job out to one of those mobile outfits. My frame has good bones, but is pretty crusty on the outside, and I suppose for about the same cost as hiring someone, I could have my own more capable blaster since I have gotten a bigger and better air compressor that can handle something like that, versus the one I had when I acquired my current sand blaster.

Concerning powder coat, a good friend of mine owns a commercial finishing shop, and the results I have seen with what powder coat can look like these days is really something else. I understand the statement about it sometimes looking thick and plasticy, and susceptible to chipping, and have seen many examples of both over the years. He's a big believer in powder coating wheels for the sake of ease of cleaning and durability, though the durability comes from prep, materials and practices used, and curing, with adequate curing seeming to be the biggest culprit in causing issues down the line, and with many shops not having a proper oven for it, the results can leave a bad taste in people's mouths. As he described it to me, when properly done and cured, its a very durable coating that will put up with years of regular driving, but to also think of it as a hard peppermint candy, really hard but when there is a good enough hit that its chipped or crack, its compromised.

There's a good chance I will end up having the wheels and a few select pieces of steering and suspension off of my '37 powder coated, but some of the more susceptible pieces that may encounter rocks and road debris, will get painted. He's a good friend of mine and has offered to do whatever I need for free or for material cost, but I believe his price for wheels, depending on condition, to be around $100 per wheel.

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Like anything, some parts were worse than others. If I need to blast parts more often than once every few years, I would have something better, but for one restoration project, it worked great. I don't understand the point of minimizing my work, but hey, it's the internet.

Sorry to have gotten this thread off course.

In my opinion, powdercoating is great, but not worth the expense on a car that stays in the garage 99% of the time and only driven a couple thousand miles per year at most.

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Curti, The answer would be no as far as filling pits prior to powder caoting. I ask my powder coater that question a long time ago in regards to something I needed to get done that was sub par. She said even the fillers with metal in them don't work.

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Curti, The answer would be no as far as filling pits prior to powder caoting. I ask my powder coater that question a long time ago in regards to something I needed to get done that was sub par. She said even the fillers with metal in them don't work.

Interesting. I am facing this same choice with wheels right now. My local powdercoater told me I could fill the pits with Allmetal, and it would work fine. If it wont, I guess that means I will be doing paint.

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Interesting. I am facing this same choice with wheels right now. My local powdercoater told me I could fill the pits with Allmetal, and it would work fine. If it wont, I guess that means I will be doing paint.

Bloo, You could get a small piece of scrap metal and drill a few dimples in it and fill it with the Allmetal stuff and see if your powder coater can run it with a batch he's already doing to see how it comes out. That way you would know for sure. I'm just going by what my powder coater told me and she's been doing it for a long time. You never know until you try it.

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Curti, The answer would be no as far as filling pits prior to powder caoting. I ask my powder coater that question a long time ago in regards to something I needed to get done that was sub par. She said even the fillers with metal in them don't work.

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It seems to me it is about the conductance of the filler. If you have a filler that has less magnetic field around it because it has lower conductance, you wont get as much powder sticking to it. So you really need a filler that has similar conductance properties to the steel you are filling, so there is minimal effect on the electro-magnetic field across and around the filling.

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With that said I mess with old car stuff and have parted out several cars and buy and sell early 60s Pontiac super duty stuff as part of my hobby. I have had a number of items/cars go through my hands that had components/floor undersides/frames coated with either powdercoat or POR15 or competing products. Those coatings are fine until they get a chip in them, which can happen, and when it does rust can start and then creep under the surrounding finish and it comes off in sheets.

I like Rustoleum.

Guess what I spent all afternoon today dealing with? Yup, you guessed it. Powdercoated parts from the underside of my truck. They looked fine until they got chips in them and water got underneath the powdercoating. LOTS of rust and like you said the powdercoat came off in big sections. Thank goodness these parts are just the brackets used to mount the running boards on my truck. I thought briefly about using POR15 and paint. Then I decided to scrape off all the loose powdercoat , use a wire wheel on the rust and just paint them with Rustoleum black and be done with it.